Banking

R3 CEV: A private company partnering with large banks to build blockchain infrastructure.

Developers

Applied Blockchain: London-based team that does a lot of private chain projects
Consensys Enterprise: New York-based part of Consensys that does consulting and development
Ledger Labs: Canadian blockchain group with Vitalik Buterin on the team

Privacy

MIT Enigma project: Secure, private storage and computing environment.